To calculate the amount of displacement of a detection target, a laser displacement sensor device conventionally calculates a weighted center of ht quantity of a received-light intensity distribution, and thus determines the peak location.
Patent Literature 1, providing a conventional technology, discloses an optical displacement meter with an object of providing an optical displacement meter adapted for faster measurement speed while retaining advantages in providing feedback control of the amount of light emitted from a light-emitting element and of the amplification factor of an amplifier; and the optical displacement meter includes a light-emitting element to emit light to a target, an image sensor to receive light from the target and to generate an image signal, a signal processing circuit including an amplifier that amplifies the image signal from the image sensor, and a control unit to provide feedback control of at least one of amounts of operation including an amount of light emitted from the light-emitting element and an amplification factor of the amplifier, based on the image signal from the signal processing circuit, where the at least one of the amounts of operation in the feedback control has a variable range that is configurable, and the control unit sets, in a variable range configuration mode, an appropriate variable range for the amount of operation, based on data on the amount of operation for a predetermined time period.